The work of this group is focused on tissue engineering and biomaterials science with a unique focus on the development of new degradable polymers. During the last years, we established the feasibility of preparing "pseudo"-poly(amino acids), amino acid derived. degradable polymers in which individual amino acids are linked by non-amide bonds. Among the pseudo-poly(amino acids), we identified a number of new polymers that exhibited good engineering and physicomechanical properties, as well as a high degree of biocompatibility. For example, tyrosine derived polycarbonates were shown to be promising materials for implantable drug delivery systems and orthopedic implants, copolymers of the natural amino acid L-lysine and poly(ethylene glycol) were successfully used as drug carriers, and polymeric conjugates of cis-hydroxyproline were prepared and found to exhibit powerful antifibrotic activity. We are also engaged in a detailed investigation of the biological properties of pseudo-poly(amino acids), including toxicological testing, cell-polymer interactions, and the effect of surface properties on the attachment and growth of various cell lines. The insights gained from these basic studies are used to create optimized polymeric scaffolds (sponge-like implants) for tissue reconstruction and tissue engineering. Thus, our long-term goals are to contribute to a better understanding of the interactions of pseudo-poly(amino acids) with living tissues and to use the knowledge gained to develop optimized polymeric implant materials for a wide range of medical applications.